


blacklight heat

by gaybreadstick



Category: Assassin's Creed - All Media Types, Prototype (Video Games)
Genre: Alpha! Alex Mercer, Alpha/Beta/Omega Dynamics, Implied/Referenced Rape/Non-con, M/M, Mating Cycles/In Heat, No mpreg, Non-Traditional Alpha/Beta/Omega Dynamics, Omega! Desmond Miles, One-Shot, alex is not a dick, desmond thinks alex is hot
Language: English
Status: Completed
Published: 2017-01-26
Updated: 2017-01-26
Packaged: 2018-09-19 23:16:00
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 4,296
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9464840
Author URL: https://archiveofourown.org/users/gaybreadstick/pseuds/gaybreadstick
Summary: Desmond is doing some routine scouting around the city when his heat sets in. He tries to get back to base before he's tracked down, but things don't quite go according to plan.





	

**Author's Note:**

> This is crossover. This does not happen during any specific timeline in either respective fandom.  
> Also horrifically un-beta'd.  
> Enjoy!

“Desmond! Desmond, are you there?” a voice rang out from the tiny earpiece. He groaned as he turned over onto his side, gritting out a small “ _shit_ ” as he did so. Desmond had been up on a skyscraper just minutes ago surveying the night life of the city; the next, he was scrambling towards the ground in an attempt to get back to the hideout before someone caught his scent. Desmond didn't want to think about being the next possible assault victim on tomorrow's news reel. He also didn't want to hear Shaun and Rebecca scolding him for not sticking with his medication to inhibit his heats. He barely made it to the closest alley safely before collapsing against the brick building and sinking to the ground.  
“Desmond?” The voice came again. The assassin frowned at the worried tone in Rebecca's voice.  
“I’m.. here..” he panted, trying to even his breath.  
“What happened?”  
“Heat.. kicking in,” he choked out. He could hear a small string of profanities on the other end in the background. Shaun came on the mic.  
“Okay Desmond, stay calm. We’ll get a pinpoint on your location and get you out of there. Find a good hiding place.”  
“I already _am_ calm,” he snarled, not feeling calm at all. He tried to stand again. Bracing against the building for support, he began to move along the alley. He needed to hide. Immediately. The alleyway was littered with dumpster bins, trash cans and other miscellaneous garbage. Deciding it probably wasn't wise to try and hide in a bin, especially inebriated, he turned his gaze upward. A block down attached to an old apartment complex was a fire escape. Perhaps he could get up there to the roof before his heat set into full force and attracted unwanted attention. He kicked off into a half jog but his legs burned underneath his body. Each step felt weaker and more disoriented than the last. Desmond groaned to himself, feeling the unmistakable sensation of slick beginning to make its presence known in his pants.  
“Fuck,” he hissed. He was only a short distance away from the fire escape when he heard voices coming from down the alley intersection. He pivoted on his heel, eyes catching the shapes of three military personnel walking towards him. “Oh, _fuck_.”  
Like snakes slithering their way towards his nostrils, the stench of the soldiers was upon him like gunfire. The most prominent was the odor of aggression and gunpowder, no doubt an alpha. As for the other two, their scents were more lenient compared to their partner. Likely betas. He bit his lip and ducked behind the closest dumpster bin. He might have been able to take on a pack of betas, but the alpha's scent aggravated his senses and made it difficult to function. Each step closer was like a jackhammer on his mind as his omega instinct threatened to kick into overdrive.  
“ _Not now, not now,_ ” Desmond silently pleaded to himself.  
“Halt.”  
His blood ran cold.  
“Smell that?” A soldier murmured.  
“Mhm,” came a low grumble in reply.  
Desmond could only assume that the gruff tone was the alpha speaking. He squeezed himself further behind the dumpster. He wished he could vanish right there off of the face of the planet. Omegas weren’t commonly permitted on the streets without proper medication for this exact reason. Too many sexual assaults on mated and non-mated omegas running around with heat stink. Unfortunately for Desmond, too many hours in the Animus amounted to him skipping a few of those crucial medical doses and had him experiencing erratic heat symptoms. A fleeting whimper wrestled past his lips as his cock began to throb, straining against his clothes in its unfortunate confinement.  
“Back here!” The dumpster Desmond had decided to take refuge behind was suddenly shoved away. The assassin scrambled to move but was cut off by the bin rolling to the side of the alley again, effectively trapping him between it and the three military men. He looked up at each of their faces feeling his heart sink into his gut.  
“Well, well. What’s a small omega boy like you doing out here?” One of the betas cooed. The condescending tone of the man’s voice was enough to make Desmond want to heave his last meal onto the man’s boots.  
“Where’s your _alpha_ , boy?” came the sneer from the grizzly-looking alpha.  
Desmond’s ears turned red.  
“Ahh, don’t have one, do you?” The other beta mused, inching towards him, turning his rifle over in his hands.  
“Maybe we should take a closer look, just to be sure,“ the first beta grinned in a way that wasn’t unlike some sort of hyena.  
Desmond launched upward. He had no intentions of going belly up for any of these fuckers. His hidden blade shot out with a snap, but missed the target. The beta he had gone after had sidestepped him and gripped his armed wrist, wrenching it around and behind him. Desmond let out a sharp cry of pain at the forceful treatment and strain on his joints. The slick of his heat was threatening to run down his legs at any moment.  
“Go on then, check him,” the alpha said, giving a sharp nod at Desmond.  
" _Not that it would make a difference for you,_ " Desmond thought bitterly. The assassin writhed in the soldier’s grasp to no avail as the other man ripped his hood down and exposed the flesh at the base of his neck connecting to his shoulder. No marks indicating a mate. Perfectly pristine, except for the odd freckle.  
“Wrong night for you to be out and about, boy,” the alpha growled, finally stepping closer to Desmond. The assassin struggled again to free himself to no avail. He was frustrated that such a simple task was nearing impossibility for him as his heat muddled his brain.  
"I'm going to knot your ass and pump you full until you're begging." Another whimper left his body as he was forced to the ground by the three men. The alpha towered over him as he knelt uncomfortably. Desmond stared at the ground but he could hear the sound of a belt coming undone and a zipper being pulled down.  
“Come on, open up for your new alph- _aaAA_!”  
Desmond’s eyes flicked up in time to see a sharp mass of black and red pierce though the chest cavity of the alpha from behind, effectively killing him. Confusion and arousal swam circles around Desmond’s head. He felt the officers abruptly drop him and run after whatever it was that had killed the man. There were two brief, equally pained cries off to the side of the alley. Desmond's brows furrowed at the sudden absence of their scents. Gone, as if they had vanished. Left in their wake, a new scent had announced itself to his senses. An odor of metal, blood, and leather. Something powerful and dangerous. He could feel the high of the kill coming off in pulses in the air. Whatever it was, this was something higher than alpha.  
" _If that's even possible-_ " “You okay.” ****It sounded more like a statement than a real inquiry. Desmond managed a nod. He felt something slip under his arm around his back and under his knees.  
“Hang on.”  
\- x -  
Desmond was shaking and sweating by the time they arrived at a small shack on top of a roof. He was carried inside and dropped onto a creaky cot in the corner. Whoever it was cracked open a mini fridge, pulling out a bottle of water and throwing it over to him.  
“Drink,” the stranger murmured. Desmond opened the water gratefully and took a long swig, water dribbling down his chin and onto his disheveled shirt in his haste. The person flicked on a light switch. The light was faint and came from a stray lamp on a tiny desk, but it was light nonetheless. Desmond blinked as the other man finally came into view. He nearly dropped the water bottle right there. Sitting on a crate just three feet away was the _Blacklight Virus_ from Manhattan. Mint eyes glowered into his own and he shrank back, ashamed at how the gaze made his already swollen cock ache between his legs.  
“You’re-”  
“Yeah, I know.”  
“Why the _fuck_ did you save my ass?” Desmond choked out. His heat was growing more and more uncomfortable with each second. He took another gulp of water, all but squirming on the spot. The virus stood and smirked down at him.  
“You could do better than those military pricks.” Being in such a small space with the virus made it impossible to escape his scent. He must have lived here because the presence of the mutant was overwhelming. Desmond pressed a hand to his forehead. This sheer power of the virus was violently circling his omega instinct like a hurricane. The man gave off an aura of lethality. It almost vibrated in the very air around them. Whatever he was, he was stronger than any alpha he'd ever met in his life. He was beyond that. This.. This was the scent of an apex predator. He leaned backward, extending an arm in hopes of not falling over.  
“Your scent…” the virus purred, looming near, “it’s not like any other omega scent I've picked up.” Desmond blinked in confusion. The male placed a hand next to Desmond’s. He was so close he could swore he could feel the virus’ breath on his skin.  
“You don’t act like a typical omega,” the virus brought his other hand up, tracing the scar decorating the corner of his mouth with a cold finger. As he continued to invade Desmond’s space, the assassin lashed out with his blade again. This one hit its mark in the junction of the virus' neck; only, the virus did not seem deterred by the gesture whatsoever. Instead he leaned into it and moaned. “You act like an alpha,” the virus hummed nonchalantly.  
Desmond sputtered as his blade retracted into its sheath. The flesh in the mutant's neck melded together and reshaped itself to take its original form - as if nothing had happened. The assassin was too captivated with how the man just regenerated to stop the virus from suddenly ambushing his neck with a series of licks and nibbles. He could feel his icy hands grip at his sides, grinding his hips against him. Desmond moaned wantonly. Here he was, underneath the deadliest creature alive. A genetically engineered superhuman machine; and his heat was triggering his rut.  
" _This is so fucked up,_ " Desmond thought to himself. He heard the virus moan. The assassin's thoughts were dismissed as his thighs grew wetter. He clawed at the patterned back of the virus’ leather jacket. Between the fabric of their pants he could feel that the man was just as hard as he was. He wasn't certain if it was his heat or his own attractions, but he knew he _definitely_ wanted him.  
“Aah- alpha,” Desmond pleaded weakly. " _Shit,_ "  
“Give me your name,” the virus snarled in his ear.  
“Aah–” His mind went blank on the request. The sensation of the alpha’s hot cock rubbing against his own was causing his mind to spin. His body craved more physical contact - he wanted the virus' cock inside him.  
“Name, omega!” Barked the virus. At the demand, Desmond snapped to attention.  
“D-Desmond,” he managed between heavy breaths. His body tensed as the command echoed in his head.  
“Mmm,” the virus moaned. He licked his lips and looked down at the man splayed out under him. “ _Shit_ , I want to fuck you, omega,” he growled, grabbing onto Desmond’s sides and grinding harder.  
Desmond’s eyes flashed open. " _Why aren't you just doing it then?_ " he thought. His eyes met those of the male above him. Instantly he felt pinned to the spot, unable to move out from the predatory stare.  
"Desmond... _Let_ me breed you." The assassin tensed. The alpha was waiting for an answer but it was obvious he was starting to grow impatient. Desmond swallowed at the sight of small black tendrils teasing their way out of the virus' body and around Desmond's closest limbs. The man let out a low growl. From where he was, he could see pointed fangs gleaming in the corners of the mutant's mouth. _Fuck_ , this guy is hot.  
"What.. what do I call you?" Desmond panted. _What was the name that they were always broadcasting on those PSAs?_ "Zeus..?"  
An arm shot out and wrapped around the omega's neck with choking force. Tendrils like solid ink wrapped around the human arm the virus had, gave it bulk and effectively pinned Desmond to the cot.  
" **Don't** ever call me that." Those deadly fangs were bared now. Desmond watched them as they loomed forward. "Call me Alex."  
" _Alex_..." Desmond gasped. He squirmed as air suddenly became hard to obtain. The virus took note of the suffocating omega and released him. The the tendrils that had spawned from the virus fluidly retracted into his body. Desmond wasn't certain where they were coming from.  
The omega rubbed against the clothed cock of the virus. His thoughts briefly flicked back to Shaun and Rebecca back at the hideout, but it died as he realized that he had left the earpiece - and only way to track him - in the alleyway. It would take them hours to follow him from there. He looked up at Alex, noticing the small patch of collarbone peeking out from behind the propped collar. Well, if he was going to allow this alpha to fuck him, he mind as well get a good look at what _exactly_ he was dealing with.  
"Aah- Alph- Alex.." Desmond panted, starting to feel hot. " _Fuck, my mind's a mess.._ "  
The faintest hint of confusion fluttered over Alex's face as he tried to decipher what the omega was asking. Desmond lifted a hand and grasped the zipper to Alex's hoodie, dark eyes and looking up at him. A grin spread across the alpha's features. He leaned back and allowed Desmond to pull the zipper down. The assassin palmed the virus' body through the thin white shirt underneath. Impatient, Alex all but tore off the buttons. As soon as he was free from the confines of the his undershirt he shrugged off the layers, leaving his torso exposed and ready for the omega's prying eyes.  
" _Ohhh fuck-_ " Desmond felt his face flush as his hand pressed against the virus. He wasn't sure what he was expecting out of a mutant virus, but whatever it was it wasn't the taught flesh of a human male. His body betrayed him as the last of his inhibitions finally gave way. Desmond fell back onto the cot and Alex's instinct flared to life.  
"You okay?" he asked quietly, pale eyes scouring Desmond's body to determine the source of distress.  
"I- I need, aah," he started. " _\--Your dick in me,_ " his traitorous mind finished.  
"Say it," Alex growled lowly.  
"I need your-" Desmond turned his head to the side, biting his tongue.  
Alex's lips curled into a coy smile. The omega underneath him was embarrassed. He shifted, hips between Desmond's legs. Slowly he grasped the zipper of the assassin's hoodie.  
"..Is this okay," he asked quietly.  
Desmond's eyes immediately locked on the virus' at the inquiry. A thousand questions crossed his mind at once but he was quickly brought back to reality.  
"I'm a prick, and _fuucck_ do I want to pound your ass, but I'm not going to just take it like some brainless fuck." he smirked.  
Desmond's breath hitched at the gesture. He glanced down at the zipper still held in Alex's fingers before looking back up and meeting Alex's gaze, nodding.  
The virus tugged the zipper down, pushing the hoodie off of the assassin's shoulders. Desmond shifted himself to escape the suffocating confines of the fabric, arms raising afterward. Alex took the hint and grabbed the hem of the grey eagle-print shirt and tugged it over the man's head in a single movement. He paused, noticing the slick sweat that had collected on the back of the shirt before discarding it off to the side.  
The assassin was about to go after his jeans before his wrist was grabbed by a strong hand.  
"Don't want you injuring yourself," Alex said, unbuckling the hidden blade from his arm and tossing it down with the man's clothes.  
Each gentle touch Alex made with the assassin made Desmond feel like his skin was on fire. His heat was in full swing now, clouding his mind and causing him to let out a needy whine.  
"Alex- Alex, please, fuck-" he groaned hoarsely, fumbling with the button of his own pants.  
"Please, what?" Alex hummed, stripping out of his clothes as the assassin struggled. He slid his pants down his narrow hips with relative ease. His cock bobbed as it sprang free from its confinement, head swollen and red and leaking. Desmond's gaze fell on the gratuitous member and his own twitched in excitement.  
" _Stop teasing me and fucking_ fuck _me already you bastard!_ " he thought, but the only words he could manage were "Please.. Fuck me."  
A low rumble emitted from the virus' throat. He pushed Desmond's hands away from his pants, making quick work and almost tearing them off of the man's lithe frame.  
Alex looked down at Desmond's cock. An eyebrow raised at how hard it was. _How had Desmond held off for so long?_ He wrapped his fingers around it, giving a few sharp jerks.  
"Aah-!" Desmond gasped, trembling at the sensation. Alex lowered himself next to the omega's hips, looking up at him and giving the man a wicked smile before running his icy tongue up the underside of the assassin's heated dick.  
The omega arched off of the cot with a keening groan. The virus snorted and forced his hips back down, taking the head of his cock into his mouth and allowing the underside to glide over the wet muscle in his mouth. Desmond slapped a hand over his mouth, sparks igniting in the pit of his gut and mind. The virus glanced up and wanted to laugh.  
"Nobody's around, let me hear you," he said. Desmond felt a thick appendage tugging his hands away from his face. Alarmed, he cracked open his eyes to see the shiny black ink of Alex's tendrils wrapping around his wrists. He jerked his arms in an attempt to slip out of the binds but they held strong. _Where were these coming from?_ From his position on the cot it was impossible to tell.  
"Shh, don't worry," Alex smirked with another lick to the tip of Desmond's dick. He reached down and stroked his own cock while his mouth worked the assassin. Above him he could hear the airy whimpers and faint profanities uttered under his breath. A devilish expression danced across the virus' face as he relaxed his throat and allowed Desmond's cock to slip into it. The omega gave a sharp cry as his member slipped from Alex's mouth with a wet pop.  
"Alex-"  
"Turn over," growled Alex, wiping the string of saliva hanging from his mouth.  
"Mmf-"  
" _ **Present, omega**_!" roared the virus, his tendrils releasing Desmond and flexing into sharp claws at the points of his fingers. Desmond's mind snapped into focus at the command, flopping over onto his stomach as fast as his inebriated state would allow.  
"Ass up."  
Desmond craned his back slightly, suddenly aware and self-conscious of the position. Alex snorted and slammed a hand into the flat of the assassin's back. The man cried out as his head was pushed down against the cot.  
"I said, ass _up_." The virus rubbed his cock against Desmond's slick hole, shuddering at the pleasing feeling it sent through him. The man beneath him responded by pushing his hips back against him. Alex smirked and gave his ass a light slap.  
"Look at you, eager to get started," he cooed.  
Desmond felt a pang of humiliation shoot through his core that ended in a twitch at the base of his cock. He weakly gripped the blanket on the cot. " _Shut up,_ " he thought.  
Alex rutted his member against the omega, the natural slickness of Desmond's heat lubricating him and causing his grinding actions to slip. Thin tendrils rose from Alex's form and wrapped around the assassin's thighs to keep him steady.  
"Alex, _please_ -" came the omega's pained cry.  
The virus angled himself up against Desmond's opening before pushing the head of his cock into him.  
Desmond tensed instantly at the intrusion. "O-oh, _ohhh_ ," he moaned into the blanket.  
"Fuck," the virus moaned deeply, letting his cock slowly slide into place. Desmond's body twitched as Alex moved in to the hilt. He paused a moment and Desmond shuddered underneath him. Cautiously he gripped the omega's hip, bracing himself with his other hand against the wall.  
He began to move, sharp jerky movements before setting into a rhythm. The air quickly was filled with the scent of mixing alpha and omega and the sounds of Desmond's desperate whines.  
"You're -- So tight, ah-" Alex said between panting breaths. Desmond seemed to want to reply but was unable to make a comprehensive sentence.  
Alex slowly picked up the pace, hips snapping forward and slapping against Desmond loudly. The omega panted with each thrust, clawing weakly at the surface below him. The virus groaned, claws tensing and cracking into the foundation of the wall above Desmond's head. The omega glanced up to see the silver and black talons embedding themselves in the concrete. The display of strength generated another twitch in his cock.  
"Fuck--"  
The assassin could feel Alex's knot beginning to swell and he braced, whimpering.  
"Alex--"  
"I'm close, Desmond.."  
" _Alex_ , I-"  
"Aah-"  
" _Mark me, Alex_!"  
The virus faltered slightly, looking down at the assassin.  
"Mark you?"  
"Yes, _fuck, don't stop_ -"  
"Are you sure-"  
"YES, mark me! _Please!_ Fuck!!"  
Alex snarled at the insistent demand but kept his pace and evaluated the flesh on Desmond's shoulder. It was a clean slate. Impressive that the omega hadn't been swept up by a higher partner until now. Usually most omegas were snatched up by the first person they had the misfortune of experiencing their heat with. He glanced down at the scar on the assassin's lip. He briefly wondered if that was from a potential candidate that he had managed to get away from.  
"Aa- Alex!"  
The virus lurched forward over Desmond, sharp fangs embedding themselves into his tender flesh. The pain that rocketed through Desmond's shoulder went straight to his groin, shoving him over the edge with a final cry. His cock pulsed and cum splattered onto the cot, steady drops dribbling out the tip. Desmond's body clamped down on Alex's knot with his orgasm, bringing the alpha over the edge. The force of the sensation flowed through his tendrils and extremities. His body almost seemed to ripple with the effect. His fangs elongated in the brief intense moment, breaking the skin and puncturing Desmond's nape and ripping a pained wail from Desmond's throat.  
As they both came down from the high, Alex released his hold on the omega. Blood welled up where Alex had marked him. The virus gently ran his tongue over the punctures, causing Desmond to shudder. He reached under the assassin, giving his spent cock a few finishing pumps.  
"Fuck.." Desmond panted.  
"Come here," Alex grunted, rolling over onto the cot and bringing Desmond with him. Alex winced at the awkward tugging on his knot until they settled into a comfortable position. He looked down at the omega he had just claimed. This was _his_ omega now. He sighed, frowning. What had he done. He couldn't _claim_ an omega. He wouldn't be able to fill the man's needs if he was on the run from the military all the time, viral infectious effects aside. Who knew how long Desmond's heat would last? He slapped a hand over his face.  
" _Idiot,_ " he thought.  
The assassin lay still with his back to Alex's chest, still panting. He had just insisted Alex - the _Blacklight Virus_ \- to claim him. As if he didn't already have a target board on his back already. If anyone found out where his mark came from the military would use him as bait. Even then, there was no guarantee that the alpha would come after him to protect him. The thought made his heart sink slightly.  
He thought about the hideout across town.  
He could harbor Alex there, at least until his heat died down again.  
Shaun and Rebecca would have some words about that, no doubt.  
"Look, ah," he heard the virus start behind him. "I'm not sure what you think _this_ ," he gestured to their locked bodies, "is, but I'm not sure I'm exactly what you were looking for in a mate."  
Desmond sat up, causing Alex to grit out a " _Careful-_ " from the pull on his knot.  
"I know, you're wanted too,"  
Alex looked over at him. "Too?"  
"Yeah. I've got a place across town where we can hide, at least until _this_ ," he gestured to his flushed body "dies down."  
Alex swallowed and after a moment's pause, nodded. 

\- x-

"There you are! Next time, tape the earpiece to your head so we can track you down. It's not easy find your needle in the haystack of this city," Shaun sighed as Desmond walked into the small room.  
"Desmond?" Rebecca questioned, cocking her head. "Is something wrong?"  
Desmond stood there in the doorway, hands in his pockets looking at Shaun and Rebecca with a guilty expression.  
"I'd... Like you to meet someone," he started slowly.  
"You didn't," Shaun groaned, swiveling towards him in his chair.  
" _He did_."


End file.
